History of the Delta Launch Vehiclehttp://kevinforsyth.net/delta/weblog
Current Delta NewsSat, 31 Jan 2015 04:21:31 +0000en-UShourly1http://wordpress.org/?v=4.1.13Delta II delayed againhttp://kevinforsyth.net/delta/weblog/?p=638
http://kevinforsyth.net/delta/weblog/?p=638#commentsSat, 31 Jan 2015 04:21:31 +0000http://kevinforsyth.net/delta/weblog/?p=638The January 30 launch attempt for SMAP was postponed when some loose insulation was found on the first stage. This is a not-uncommon occurrence and is usually a quick patch job to repair. The next attempt is set for Saturday morning.
]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=6380Brief returnhttp://kevinforsyth.net/delta/weblog/?p=635
http://kevinforsyth.net/delta/weblog/?p=635#commentsThu, 29 Jan 2015 16:37:02 +0000http://kevinforsyth.net/delta/weblog/?p=635Yes, it has been an awfully long time since a fresh posting. This is the obvious consequence of 1) the Delta II program winding down to a very sporadic last few flights, and 2) me having paying gigs that take precedence over this labor of love. So, in brief:

Today’s launch of Delta flight 370 was scrubbed before release of the T-minus 4 minute hold due to upper level winds. A 24-hour turnaround is expected to have a 90% chance of favorable conditions. The United Launch Alliance two-stage Delta Med-Lite vehicle will carry NASA’s Soil Moisture Active Passive environmental monitoring satellite into a polar orbit from Vandenberg Air Force Base. As ever, SpaceflightNow.com will carry live coverage.

]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=6350Delta II reaches the on-ramphttp://kevinforsyth.net/delta/weblog/?p=621
http://kevinforsyth.net/delta/weblog/?p=621#commentsMon, 03 Oct 2011 22:20:19 +0000http://kevinforsyth.net/delta/weblog/?p=621NASA has announced the modification of its NASA Launch Services (NLS) II contract with United Launch Services, putting Delta II back on the menu. Parts for five Delta II vehicles have already been manufactured, and are now in storage; this contract modification will enable ULS to offer them to NASA for launch services between now and June 2020. [NASA Contract Release C11-044, 30-Sep-11]

The announcement means that the Delta II era might last beyond the launch of NPP, currently slated for 27 October. Of course, since the production line is out of commission, these five vehicles will be the last—but at least they have a chance to serve their purpose, rather than gather dust. Any remaining Delta II launches are expected to take place at Vandenberg’s SLC-2W.

A first attempt on Thursday was scrubbed due to upper level wind shear, and Saturday’s launch had to contend with much the same issue: a wind shear at 15–22,000 ft altitude, right around the transsonic region of the Delta II flight path, when the vehicle would be most vulnerable. Fortunately the shear was less severe than Thursday’s and flight controllers were able to work around it, targeting the second of two instantaneous launch windows. The official range liftoff time was 09:08:52.775 EDT.

The twin spacecraft of GRAIL will take nearly four months to reach the Moon, using a circuitous path through the Earth-Sun Lagrange point 1 to help refine and synchronize their orbits to each other. The long cruise will also allow the spacecraft to eliminate any outgassing that could be mistaken for gravitational effects. This will enable them to make highly accurate gravimetric measurements of the Moon in order to map its complete internal structure for the first time in over 50 years of lunar exploration.

According to Jonathan’s Space Report, the Aerojet-built second stage ended up in a 0.88 x 1.05 AU x 0.01 deg heliocentric orbit, with a period of around 347 days. Based on that approximation, the stage could sail past Earth again in 19 years.

The two-stage launch vehicle, with its oversized GEM-46 booster motors marking it as a “Heavy” model, extended the Delta II reputation for reliability, now standing at 95 consecutive successful launches. One Delta II launch—next month’s NPP from Vandenberg—remains on the schedule. United Launch Alliance continues to seek customers for the final 5 Deltas in storage.

]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=6130Scrub!http://kevinforsyth.net/delta/weblog/?p=607
http://kevinforsyth.net/delta/weblog/?p=607#commentsThu, 08 Sep 2011 13:12:31 +0000http://kevinforsyth.net/delta/weblog/?p=607A strong shear in the upper level wind conditions has led to a 24-hour turnaround for NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission to the Moon. The next launch opportunity is on Friday, 9 September, with two instantaneous launch windows at 12:33:25 and 13:12:31 UTC.

Update: Friday’s attempt has been postponed “to allow additional time to review propulsion system data from Thursday’s detanking operation.” Launch windows for Saturday, 10 September, are 12:29:45 and 13:08:52 UTC. The weather report for that day gives a 60% chance of conditions favourable for launch, an improvement over Thursday and Friday’s 40%.

]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=6070Next launchhttp://kevinforsyth.net/delta/weblog/?p=598
http://kevinforsyth.net/delta/weblog/?p=598#commentsMon, 15 Aug 2011 18:05:15 +0000http://kevinforsyth.net/delta/weblog/?p=598The next Delta II launch will send NASA’s Gravity Recovery And Interior Laboratory (GRAIL) mission toward the Moon. There, GRAIL will “create the most accurate gravitational map of the Moon to date, improving our knowledge of near-side gravity by 100 times and of far-side gravity by 1000 times.” This high-resolution map will help scientists to better understand the Moon’s internal composition. The twin spacecraft, GRAIL-A and GRAIL-B, completed their final inspections at the Astrotech facility on Tuesday, 9 August, and will be transported to Space Launch Complex 17 this week.

The two-stage Delta II Heavy launch vehicle has been stacked on pad 17B since 20 May, and pre-launch testing has been in work since then. The launch period opens on 8 September.

]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=5980Mission round-uphttp://kevinforsyth.net/delta/weblog/?p=587
http://kevinforsyth.net/delta/weblog/?p=587#commentsFri, 01 Jul 2011 18:15:18 +0000http://kevinforsyth.net/delta/weblog/?p=587In lieu of immediate Delta II action—the next launch will occur no earlier than September—here is a round-up of news about current missions that began with successful Delta II launches.

Dawn (Delta 327) will arrive at Vesta on 16 July. It will remain in orbit for several months to study the asteroid before moving on to Ceres. (JPL Press Release, 23 June 2011)

Studies of samples returned to Earth in 2004 by Genesis (Delta 287) suggest that the Sun and inner planets “may have formed differently than previously thought.” (JPL Press Release, 23 June 2011)

MESSENGER (Delta 307) attained orbit around Mercury in March 2011, and so far its science return has been spectacular. Co-Investigator Scott Murchie of the Johns Hopkins University Applied Physics Laboratory (APL) will be awarded the NASA Distinguished Public Service Medal at a ceremony later this month. (MESSENGER Mission News, 22 June 2011)

And finally, one piece of Delta-related news: NASA is considering purchase of one or more of the five remaining Delta II vehicles for use of future missions, according to Space News. The loss of two NASA spacecraft to failures of the Taurus XL vehicle is a factor in the move. No word on how negotiations with United Launch Alliance are proceeding.

]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=5870Delta flight 354 – SAC-D/Aquariushttp://kevinforsyth.net/delta/weblog/?p=573
http://kevinforsyth.net/delta/weblog/?p=573#commentsFri, 10 Jun 2011 21:14:16 +0000http://kevinforsyth.net/delta/weblog/?p=573A two-stage United Launch Alliance Delta II rocket lifted off into a thick fog early this morning, Friday, 10 June 2011, from California’s Vandenberg Air Force Base. Aboard was the SAC-D/Aquarius spacecraft, a joint mission of Argentina’s National Commission on Space Activities (CONAE) and NASA. The launch vehicle performed as expected, placing the spacecraft into a circular, sun-synchronous polar orbit some 56 minutes after launch. Official liftoff time was 14:20:13 UTC.

Satelite de Aplicaciones Cientificas-D, the second SAC spacecraft to launch aboard a Delta II, is festooned with several Earth-sensing scientific instruments supplied by different countries. Primary among these is NASA’s Aquarius sensor, which will gauge ocean surface salinity levels. Data from Aquarius is expected to fundamentally impact our understanding of the world’s oceans in terms of circulation, climate, and water cycle.

This was the 94th consecutive successful launch by Delta II, a world-record series of successes dating back to May 1997. It was the first of three planned launches for Delta II this year—all of them for NASA, and the final flights on the schedule. Five Delta II vehicles remain in storage, complete and awaiting assignment.

]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=5730Next launchhttp://kevinforsyth.net/delta/weblog/?p=566
http://kevinforsyth.net/delta/weblog/?p=566#commentsTue, 07 Jun 2011 19:13:49 +0000http://kevinforsyth.net/delta/weblog/?p=566Update for 8 June: Launch has been postponed for 24 hours due to a technical issue.

The first of three Delta II launches slated for 2011 is on schedule for departure on Thursday, 9 June. The 5-minute window opens at 07:20:13 PDT at Vandenberg Air Force Base, where a two-stage Delta II 7320 stands ready to put the SAC-D/Aquarius spacecraft into orbit for the Argentina National Commission on Space Activities and NASA. The Flight Readiness Review was completed on 2 June, and loading of the Delta II second stage with hypergolic propellants was performed a day later.

]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=5660High launch costs may lead to fewer NASA missionshttp://kevinforsyth.net/delta/weblog/?p=545
http://kevinforsyth.net/delta/weblog/?p=545#commentsWed, 06 Apr 2011 22:07:18 +0000http://kevinforsyth.net/delta/weblog/?p=545With the last few Delta II missions already slated and no desire to cover the high cost of continuing that launch system, NASA now finds itself with a not-unexpected dilemma: no affordable means to get small- and medium-class spacecraft off the ground. Spaceflight Now has the full story.
]]>http://kevinforsyth.net/delta/weblog/?feed=rss2&p=5450